Technical draft study report for TOPEX satellite options study, volume 1

The use of two spacecraft for adaptation to the TOPEX mission, namely the P80-1 and the GPS phase 2 are considered. The mission involved three mission options, each option varying in payload definition, payload weight, orbital altitude and payload power requirements. The P80-1 spacecraft is an Air Force Space Test Program satellite which carries a number of payloads to an orbital altitude of 400 n.mi. at a minimum inclination of 72.5 deg, and which has an orbital life capability of three years. The GPS phase 2 spacecraft is the operational satellite for the Global Positioning NAVSTAR navigation constellation provided for all service (and commercial) use.